using GB5Shared.DTO.Framework.Login;
using GB5Shared.ListQuery;

namespace QMSDAL.Query.Matrix
{
    // ── MatrixListGuard ────────────────────────────────────────────────────────
    // Rejects list requests that omit AllocationId.
    // An unbounded scan across all tenants' matrices would be prohibitively
    // expensive and is never a valid use-case for this query.
    //
    // This guard runs before the query is built or executed, so the failure
    // is surfaced immediately rather than returning an empty result set or
    // hitting the DB with a full-table scan.
    // ──────────────────────────────────────────────────────────────────────────
    public sealed class MatrixListGuard : IQueryGuard<MatrixListQuery>
    {
        public void Validate(MatrixListQuery query, LoginDTO login)
        {
            ArgumentNullException.ThrowIfNull(query);
            ArgumentNullException.ThrowIfNull(login);

            if (query.Criteria is null)
                throw new ArgumentException(
                    "MatrixListQuery.Criteria must be set before validation.",
                    nameof(query));

            // FIX: changed == 0 to <= 0 so the sentinel value -1 is also rejected.
            // A valid AllocationId is always a positive integer.
            if (query.Criteria.AllocationId <= 0)
                throw new ArgumentException(
                    "AllocationId is required for matrix list queries.",
                    nameof(query));

            // Guard: TenantId from login must be positive.
            // This mirrors the check in BuildMatrixList and catches misuse early.
            if (login.ClientId <= 0)
                throw new ArgumentException(
                    "A valid TenantId (ClientId) is required.",
                    nameof(login));
        }
    }
}